1. Field of the Invention
The present invention relates to the production of holes in workpieces which have limited accessibility or are difficult to manipulate and particularly to the positioning of a boring tool relative to such workpieces so as to enable the accurate drilling thereof. More specifically, this invention is directed to a hand tool which, when mated with a portable motor driven drill, will engage a workpiece and accurately position and support the drill relative to the workpiece so as to enable the accurate boring thereof. Accordingly, the general objects of the present invention are to provide novel and improved methods and apparatus of such character.
2. Description of the Prior Art
While not limited thereto in its utility, the present invention has been found to be particularly well suited for performing operations on workpieces comprised of sheet metal. An example of such a workpiece is an automobile body panel which will typically be spot welded to an abutting member(s) which may, for example, be in the form of a plate. It is often necessary to replace such panels, for example in the repair of collision damage, and such replacement requires that the welds be "broken" by drilling. The "drilling out" of spot welds which hold a sheet metal panel in place is a difficult and time-consuming task which requires a relatively high level of skill.
The problem briefly discussed above, and problems presented by the need to produce through-holes in other workpieces such as I-beams and channels, has previously been addressed by providing special tools which are expensive and often difficult to use. An example of such a special tool may be seen from U.S. Pat. No. 4,540,319. It has also been suggested, but not implemented on a commercial level, to associate various types of complicated clamp devices with drills. Such clamping devices, examples of which may be seen from U.S. Pat. Nos. 1,926,788 and 2,625,063, have met with very limited success because of inherent deficiencies which will not be discussed herein. There have also been prior art devices which have attempted to employ a portable drill as a stationary drill press. Such devices, as exemplified by the disclosure of U.S. Pat. No. 2,856,799, have lacked portability and the capability of use where space was limited or where the work could not be brought to the tool.